基于Nrf2/Keap1/ARE通路研究槲皮素对小鼠年龄相关性黄斑变性的保护作用

目的：探讨槲皮素通过Nrf2/Keap1/ARE通路对小鼠年龄相关性黄斑变性的保护作用及机制研究。

方法：以昆明小鼠为研究对象，分为：对照组、模型组、槲皮素组； 眼底检查各组小鼠眼底是否出现黄白色似玻璃疣物质； OCT检查各组小鼠视网膜厚度； HE染色观察各组小鼠视网膜形态的改变； FFA观察各组小鼠眼底血管完整性； ELISA检测小鼠血清中SOD、GSH-Px、CAT活性和ROS、MDA含量变化； Western blot检测各组小鼠视网膜中Nrf2/Keap1/ARE相关蛋白的表达情况。

结果：槲皮素能使小鼠眼底的黄白色似玻璃膜疣物质减少且视网膜厚度增加(P<0.05)，视网膜血管渗漏点明显减少； 与模型组比较，槲皮素组小鼠的a波振幅、b波振幅较模型组均明显上升(P<0.01)； 槲皮素能使小鼠视网膜结构比较清晰，部分外核层发生坏死脱落，且使小鼠血清中ROS、MDA含量降低(均P<0.05)，SOD、GSH-Px、CAT活性提高(均P<0.05)； 与模型组比较，槲皮素组小鼠视网膜细胞质中Nrf2蛋白表达上调(P<0.05)，细胞核中Nrf2蛋白表达下调(P<0.05)，小鼠视网膜中Keap1、HO-1、NQO-1、GCL蛋白表达下调(均P<0.05)。

结论：槲皮素可能通过Nrf2/Keap1/ARE通路，改善视网膜光损伤后的氧化应激状态，保护视网膜功能，对年龄相关性黄斑变性具有保护作用。

Study on the protective effect of quercetin on age-related macular degeneration in mice based on Nrf2/Keap1/ARE pathway

AIM: To investigate the protective effect and mechanism of quercetin on age-related macular degeneration in mice through Nrf2/Keap1/ARE pathway.

METHODS: Kunming mice were used as research objects, which were divided into control group, model group and quercetin group. Fundus examination was showed whether yellow-white like glassy sputum substances appeared in the fundus of each group of mice; OCT was used to examine the retinal thickness of each group of mice; HE staining was used to observe the changes of retinal morphology in each group of mice; FFA was observed the fundus vascular integrity of each group of mice. The activities of SOD, GSH-Px, CAT and the contents of ROS and MDA in serum were detected by ELISA; Western blot was used to detect the expression of Nrf2/Keap1/ARE related proteins in the retina of each group.

RESULTS: Quercetin can reduce the yellow and white glassy wart substance in the fundus of mice and increase the thickness of the retina(P<0.05), and the points of retinal vascular leakage is significantly reduced. Compared with the model group, the a-wave amplitude and b-wave amplitude of the quercetin group were significantly higher than those of the model group(P<0.01); Quercetin can make the retinal structure of mice clearer, necrosis and shed part of the outer nuclear layer, and reduce the content of ROS and MDA in mouse serum(all P<0.05), and increase the activities of SOD, GSH-Px, and CAT(all P<0.05). Compared with the model group, the expression of Nrf2 protein in the retinal cytoplasm of mice in the quercetin group was up-regulated(P<0.05), and the expression of Nrf2 protein in the nucleus was down-regulated(P<0.05), GCL protein expression was down-regulated(P<0.05).

CONCLUSION: Quercetin improved the oxidative stress state after retinal photodamage through the Nrf2/Keap1/ARE pathway, protected the retinal function, and protected against age-related macular degeneration.